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ABSTRACT Ti‐rich dual spherules recovered from Segment S2 near the axial ridge (69.865° E, 24.819° S), of the southern Central Indian Ridge (CIR), Indian Ocean, were examined to understand their petrogenesis and hydrothermal‐magmatic significance. Three Ti‐rich dual spherules were identified within an 85 g sediment sample. Two of these comprise cryptocrystalline spherules containing wüstite and titanite–ilmenite–shcherbakovite (tn–il–shc) assemblages, whereas the third consists of a Ti‐rich magnetite–wüstite spherule attached to an ellipsoidal Fe–Ti‐rich cryptocrystalline clast hosting cuboidal to rhombohedral rutile crystals within silica‐rich glassy mesostasis. The high abundance of the spherules and absence of Ni enrichment argue against an extraterrestrial origin. Textural relationships, including shared interfaces between adjacent droplets, reaction rims, dendritic crystallites and localized fine‐grained zones near the attachment sites, indicate that the dual spherules formed via collision and interaction of molten Fe‐Ti‐rich droplets prior to quenching. Followed by nucleation at the liquid–liquid interface and growth within a thermal gradient. In one dual‐spherule, the molten droplet seems to have collided with a pre‐existing solid rutile‐bearing clast, suggesting entrainment of altered fragments during eruptive activity. In contrast, the mineral chemistry of Ti‐rich magnetite/wustite, rutile‐bearing clast and the presence of Fe‐rich vein indicate modification via hydrothermal processes post‐formation of the dual‐spherule. However, the studied spherules likely formed during ridge‐axis hydrothermal‐magmatic activity, where Fe‐Ti‐rich molten droplets were generated during late‐stage magmatic differentiation, dispersed into the water column and rapidly quenched to produce the observed dual‐spherules.
Agarwal et al. (Sun,) studied this question.